Uses DMA to read/write SPI blocks, while putting the current thread in Wait state.
RTOS_SPI_KL46.cpp
- Committer:
- Tomo2k
- Date:
- 2014-06-28
- Revision:
- 4:0ab62cbad3aa
- Parent:
- 2:d052724e2ad6
File content as of revision 4:0ab62cbad3aa:
#ifdef TARGET_KL46Z #include "RTOS_SPI.h" RTOS_SPI::RTOS_SPI(PinName mosi, PinName miso, PinName sclk, PinName _unused) : SPI(mosi, miso, sclk) { if (_spi.spi == SPI0) { read_dma.trigger(Trigger_SPI0_RX); write_dma.trigger(Trigger_SPI0_TX); } else { read_dma.trigger(Trigger_SPI1_RX); write_dma.trigger(Trigger_SPI1_TX); } read_dma.source(&_spi.spi->DL, false); // 8-bit SPI only uses the LSB write_dma.destination(&_spi.spi->DL, false); // 8-bit SPI only uses the LSB }; void RTOS_SPI::bulkInternal(uint8_t *read_data, const uint8_t *write_data, int length, bool read_inc, bool write_inc) { aquire(); _spi.spi->C2 |= SPI_C2_TXDMAE_MASK | SPI_C2_RXDMAE_MASK; read_dma.destination(read_data, read_inc); if (write_inc) write_dma.source(write_data+1, write_inc); else write_dma.source(write_data, write_inc); //simply start the read_dma read_dma.start(length); //Write the first byte manually, since this is recommended method (and the normal method sends the first byte twice) while((_spi.spi->S & SPI_S_SPTEF_MASK) == 0); _spi.spi->DL = write_data[0]; // 8-bit SPI only uses the LSB write_dma.wait(length-1); while(read_dma.isBusy()); _spi.spi->C2 &= ~(SPI_C2_TXDMAE_MASK | SPI_C2_RXDMAE_MASK); } #endif